Recently, data communication devices comprising housings formed partly or entirely of carbon materials have become widely used. Carbon materials have excellent characteristics of being light and strong. Therefore, it is possible by using a carbon material for the housing of a data communication device to reduce the weight and improve the strength of the data communication device.
For example, there is a case where the housing of a tablet computer comprises a base formed of a carbon material such as CFRP and circumferential edges formed of a resin material such as glass epoxy resin. In this case, a resin material is attached to each of the edges of a stretched, thin plate-like carbon material (base). The carbon material and the resin material are integrally attached to each other by gluing or welding.
Here, in the case of attaching a thin metal plate and a resin material to each other, it is possible to increase an attachment strength by providing a projection (anchor) in the metal plate and increasing an attachment area. Therefore, it is possible to easily obtain a desired attachment strength without significantly increasing a portion (overlapping portion) of the metal plate and the resin material in which the metal plate and the resin material overlap and become continuous with each other. On the other hand, in the case of a carbon material, it is difficult to perform fine processing such as processing into a thin plate having a projection (anchor) as compared to the metal plate. Therefore, to increase the attachment strength of a thin plate-like carbon material and a resin material, an overlapping portion greater than that of the case of a metal plate is required. That is, a housing comprising a base formed of a carbon material will have circumferential edges more expanded than those of a housing formed of a metal material for overlapping portions, and thus the housing is likely to have dead spaces.
In a thin tablet computer, built-in components such as a battery and a communication module take up the edges of the tablet computer, that is, up to the vicinity of the overlapping portions. Further, it is also necessary to provide components such as a wireless LAN antenna away from a carbon material having high conductivity so that the antenna performance will not be affected by the carbon material. Therefore, in a housing comprising a base formed of a carbon material, it is necessary to use circumferential edges including overlapping portions effectively for arranging an antenna. Note that, in the case of providing an antenna on a base formed of a carbon material, for example, processing such as forming a notch in a portion of the base overlapping the antenna is necessitated in consideration of the influence of the base on antenna performance. In this case, there is a possibility that the processing will weaken and spoil the appearance of the housing.